Home theatre suggestions

[nmycon]

Hey,

I am 16 (just turned 16 actually, in january) and am FINALLY piecing together my own "bedroom theatre"

My "work" room (it has my desk and MacBook, but with the PS3 and TV, I don't get as much work done as I should) is about 10.5 ft long and 9 ft wide

This is what I have managed to get so far (all coming out of my own pocket by the way):

32" LG 720p TV (32LG20 1366x768)
Yamaha RXV365 5.1 Reciever
PSB 300 Model Speakers (only 1 pair of speakers for now)
Dual CS-515 Belt-drive turntable (with phono preamp, receiver has no phono)
and 40 GB PS3

anyways, I was wondering, for the rest of the speakers, i was planning to get PSB for the rear and centre channel speakers just to keep the brand the same so that the sounds from each speaker will (hopefully) sound better together... is this the right way to go or am i thinking the wrong way?

also, does anyone know of any cheap but decent subwoofers... thats next on my list before speakers... i want some added bass when i'm listening to my vinyl!

any help is greatly appreciated, will probably post pics (of my messy room) once the whole thing is done...